Prolonged-release multimicroparticulate oral pharmaceutical form

ABSTRACT

Modified-release multimicroparticulate pharmaceutical form capable of maintaining the modified release of the active principle in an alcoholic solution and of resisting attempts at misuse.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No. 11/802,610, filed May 24, 2007, which claims priority to U.S. Provisional Application No. 60/802,795, filed May 24, 2006, all of which is incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

The field of the present invention is that of pharmaceutical forms with modified release of medicinal active principles (APs) intended for oral administration, containing at least one AP, capable of maintaining a modified release of the AP in an alcoholic solution, i.e. not subject to rapid dose dumping in the presence of alcohol; furthermore, they contain anti-misuse means.

The APs considered are pharmaceutical and/or veterinary APs, for example those classified in the category of stupefacients, analgesics or narcotics. Abuse of these APs can give rise to drug addiction-related behavior.

The present invention relates more particularly to the pharmaceutical forms of the type targeted in the paragraph above and comprising a plurality of reservoir microparticles. The present invention relates even more particularly to the pharmaceutical forms for which it is advised not to consume alcohol during administration.

The objective targeted by the present invention is that of improving the multimicroparticulate pharmaceutical forms designed to resist attempts to misuse them, the improvement consisting in preventing the patient from experiencing rapid dose dumping in the presence of a large volume of alcoholic solution.

The invention also relates to a method for preparing the pharmaceutical forms mentioned above.

Context of the Invention

The advantage of modified-release pharmaceutical forms for the administration of a drug is well known. They make it possible in particular to ensure more thoroughly that the therapeutic need is covered, because the useful plasma concentration of AP can be maintained for a longer period of time than in the case of immediate-release forms. Furthermore, they make it possible to limit the height and the number of the peaks of plasma concentration of AP, which decreases the toxicity of the drug and/or reduces the side effects thereof. The advantage of modified-release forms is, in this respect, particularly marked for active principles with a narrow therapeutic window. Moreover, these systems make it possible, by virtue of their increased duration of action, to limit the number of daily intakes, which decreases the restrictions on the patient and improves compliance with the treatment.

Systems for prolonging the action of a drug have thus been sought, and the references concerning this objective are numerous. In this regard, the work by Buri, Puisieux, Doelker and Benoît: Formes Pharmaceutiques Nouvelles [Navel Pharmaceutical Forms], Lavoisier 1985, p. 175-227 will be consulted.

However, it appeared that the consumption of alcohol in parallel with the administration of a modified-release (or MR) pharmaceutical form can lead to the accelerated and potentially dangerous release of the AP in the patient. For APs such as opiate-based analgesics, the side effects following too rapid a release of a high dose of AP and the concomitant consumption of alcohol lead to serious consequences which can even sometimes put the patient's vital prognosis in danger.

A modified-release form must therefore ideally be capable of preventing the accidental accelerated release of the AP in an alcoholic solution.

Moreover, a modified-release form must be able to block the intentional misuse of certain active principles such as opiates, which poses a real public health problem.

Intentional misuse is encountered mainly in the case of drug addiction and chemical dependency. In these two cases, individuals who have the intention of misusing an oral solid drug will generally apply themselves to extracting the AP from the modified-release form in order to obtain a rapidly acting product.

The MR pharmaceutical form must obstruct three methods of intentional misuse:

1. inhalation or oral administration of the form previously formulated as an immediate-release powder.

2. Parenteral injection of a small volume of liquid containing the AP extracted from the MR form.

3. Oral administration of a beverage containing the AP in dissolved form.

For cases 2) and 3), the production of a liquid form from a solid oral drug generally involves a step consisting of extraction, in an aqueous or organic phase, of the targeted AP. This extraction is generally preceded by crushing.

Methods of administration 1) by inhalation or 2) by injection are particularly suitable for drug addicts because they are methods which make it possible to accentuate the effects of the AP and which promote its rapid absorption in the body. When the powder obtained by crushing is aspirated via the nose or dissolved in water and injected, the desired effects, drugged feeling or feeling of euphoria, of the AP manifest themselves very rapidly and in an exacerbated manner.

Method 3) also constitutes a particularly serious abuse which affects adolescents and which concerns analgesic APs, more especially morphine and opiate derivatives. Using a highly alcoholic beverage and an opiate analgesic, in particular oxycodone, with a few manipulations, it is possible to extract the opiate analgesic, which can then be absorbed by a drug addict.

The misuse of solid oral drugs can also be observed when, instead of being rapidly swallowed in accordance with the prescription, the drug is chewed before being swallowed, thus bypassing the step of slow disintegration in the stomach and leading to dose dumping.

Thus, in addition to a release profile which makes it possible to prolong and/or to delay the absorption of the AP, an MR release form must make it possible to prevent intentional or unintentional misuse of the AP. In particular, the MR form must simultaneously have the following four essential properties:

a) must not result in an accelerated release of the AP in an alcoholic solution, as might occur, for example, in a patient having accidentally absorbed the drug with an alcoholic drink;

b) must be difficult to crush into the form of an immediate-release powder, in order, for example, to prevent inhalation of the AP;

c) must be difficult to extract in a small volume of liquid, thus preventing parenteral injection of the AP;

d) must not lead to massive solubilization of the AP in a beverage which may or may not be alcoholic, thus preventing oral administration of the AP in an IR form even after a long contact time.

In order to avoid massive dose dumping in the presence of alcohol, which may result in particular from an intentional or unintentional misuse, unpublished application FR 06 50566 describes multimicroparticulate pharmaceutical forms capable of resisting accidental dose dumping in the presence of alcohol, in particular so as to respond to the preoccupations of health professionals faced with accidents caused by this dose dumping in vivo, in patients who have ingested a prolonged-release pharmaceutical form at the same time as a large dose of alcohol. These modified-release forms have the property of maintaining the modified-release of the AP even in a large volume of alcoholic solution (50 to 900 ml). However, these forms are not designed to resist attempts to misuse them, in particular by crushing a dry form, possibly followed by extraction in a liquid medium.

The teaching of this application FR 06 50566 constitutes considerable progress since it proposes a first solution to the problem a) mentioned above. However, it does not propose any solution for problems b), c) and d).

Unpublished application FR 05 53437 describes multimicroparticulate pharmaceutical forms designed so as to be resistant to misuse, in particular intentional misuse. These fraudulent forms of abuse of oral drugs involve various steps (crushing, extraction), and said application describes controlled-release oral forms comprising anti-misuse means:

-   -   the coated microparticles of AP comprise a coating layer which         confers resistance to crushing;     -   in addition, the pharmaceutical forms of this application         contain a viscosity agent which makes it very difficult if not         impossible to extract the AP in a liquid medium;     -   finally, they optionally contain a quenching agent.

These forms exhibit resistance to extraction in a small volume (for example, 2.5 ml) of an aqueous or alcoholic medium. However, these forms are not suitable for resisting the dose dumping which can occur in the presence of a large volume of alcoholic medium.

Thus, this invention does not propose a technical solution which makes it possible to simultaneously satisfy the four conditions a), b), c) and d) recalled above.

In this context, it must be noted that there exists a need for a modified-release multimicroparticulate pharmaceutical form for the oral administration of AP, capable, firstly, of maintaining the modified release of the AP in an alcoholic solution (unintentional or accidental misuse) and, secondly, of resisting attempts at intentional misuse.

OBJECTIVES OF THE INVENTION

One objective of the invention is to provide novel oral solid drugs which meet the specifications recalled above.

Another objective of the invention is to provide novel oral solid drugs which do not produce a significant acceleration of the release of the AP in an alcoholic solution and have means which make misuse of the AP very difficult or even impossible.

Another objective of the invention is to provide novel oral solid drugs which do not produce a significant acceleration of the release of the AP in an alcoholic solution, the misuse of which, by crushing or after extraction of the AP in a small volume of solvent, will be made difficult or even impossible.

Another objective of the invention is to provide novel oral solid drugs having the following characteristics:

-   -   under normal administration conditions, these oral solid drugs         have a therapeutic effect, for example for 12 or 24 hours;     -   any attempt at abusive extraction of the AP will result in a         non-immediate-release form or in an extracted product which is         difficult to use, to such an extent that, after ingestion of the         drug, rapid absorption of the AP into the bloodstream will not         be possible.

Another objective of the invention is to provide novel oral solid drugs which make it possible to prevent fraudulent abuse of the properties of the AP that it contains, making it difficult to administer the drug orally, nasally and/or by injection (intravenous, subcutaneous, intramuscular, etc.) outside the therapeutic context.

Another objective of the invention is to provide novel oral solid drugs which make it possible to prevent misuse while at the same time guaranteeing for the patient normally followed up, a quality of treatment, in particular a dose, in accordance with said individual's needs.

Another objective of the invention is to provide a method for the manufacture of oral solid drugs which resist immediate AP dose dumping in the presence of alcohol and which comprise anti-misuse means.

DEFINITIONS

For the purpose of the present disclosure of the invention:

-   -   modified-release form or MR form are synonyms and comprise:     -   reservoir systems, i.e. systems in which the release of the AP         is controlled by a coating surrounding the AP;     -   matrix systems, in which the AP, intimately dispersed in a         matrix, for example a polymer-based matrix, is released by         diffusion and/or erosion;     -   “active principle” and the abbreviation “AP” denote both a         single active principle or a mixture of several active         principles. The AP can be in free form or in the form of a salt,         an ester, a hydrate, a solvate, a polymorph, isomers or other         pharmaceutically acceptable forms;     -   the alcohol ingested may come from various alcoholic beverages         or drinks such as beer, wine, cocktails, spirits, or mixtures         thereof;     -   in vitro, the term “alcohol”, unless otherwise specified,         represents ethanol, and the term “alcoholic solution” or         “alcoholic medium” represents an aqueous solution of ethanol;     -   “reservoir microparticles” denotes microparticles comprising AP         and individually coated with at least one coating which allows         modified release of the AP;     -   “microparticles of AP” denotes, without distinction, reservoir         microparticles and/or microparticles comprising AP which are not         necessarily coated;     -   “microparticles of viscosity agent” denotes microparticles         comprising at least one viscosity agent and, optionally, other         excipients, with the exclusion of the AP;     -   “quenching agent” denotes a complexing agent, a deactivating or         inactivating agent, a chelating agent, a precipitating agent, or         else a scavenger, capable of interacting with an AP and         deactivating it;     -   “microparticles of quenching agent” denotes microparticles         comprising at least one quenching agent and, optionally, other         excipients, with the exclusion of the AP;     -   “microparticles” denotes, without distinction, reservoir         microparticles, uncoated microparticles of AP, microparticles of         AP, microparticles of viscosity agent and microparticles of         quenching agent, taken alone or as a mixture;     -   the in vitro dissolution profiles are realized according to the         indications of the European pharmacopoeia (5^(th) edition,         §2.9.3) in which the dissolution media conventionally used are         described. In order to simulate the gastric medium of an         individual having absorbed a large amount of alcohol, the         dissolution medium is modified by the addition of ethanol (q.s.         for 10% to 40% by volume);     -   the term “modified release” means that the release of the AP in         vitro is such that 75% of the AP is released in a period of time         of greater than 0.75 h, and preferably of greater than 1 h, and         more preferentially of greater than 1.5 h. A modified-release         pharmaceutical form can, for example, comprise an         immediate-release phase and a slow-release phase. The modified         release can in particular be a prolonged and/or delayed release.         Modified-release pharmaceutical forms are well known in this         field; see, for example, Remington: The science and practice of         pharmacy, 19^(th) edition, Mack publishing Co., Pennsylvania,         USA;     -   “immediate release” means that the release is not of         modified-release type and denotes the release, by a form, of         most of the AP in a relatively brief period of time: at least         75% of the AP is released in 0.75 h, preferably in 30 min;     -   the similarity between two dissolution profiles is evaluated by         means of the similarity factor f₂ as defined in the document         “Quality of modified-release products” of the European Agency         for the evaluation of medicinal products, document referenced         CPMP/QWP/604/96 (Annexe 3). An f₂ value of between 50 and 100         indicates that the two dissolution profiles are similar;     -   “agglomerate” or “granule” relates to structures comprising a         plurality of microparticles bound to one another by an agent D,         optionally comprising other excipients, the diameter of the         agglomerates or granules preferably being less than 8000 μm;     -   the multimicroparticulate oral pharmaceutical forms according to         the invention consist of numerous microparticles, whose size is         less than a millimeter. The diameters of the microparticles with         which the present disclosure is concerned are, unless otherwise         indicated, mean diameters by volume. These multimicroparticulate         forms can be provided and adapted by those skilled in the art in         any of the acceptable pharmaceutical forms, such as tablets,         gelatin capsules, sachets, suspensions to be reconstituted;     -   the term “unit form” is intended to mean the pharmaceutical form         which contains one dose of AP which can be in the form, for         example, of tablets, gelatin capsules, sachets, suspensions to         be reconstituted;     -   the term “dose dumping” or “rapid dose dumping” is intended to         mean an immediate, or significantly accelerated, and unwanted,         release of the dose of AP after ingestion per os.

BRIEF DESCRIPTION OF THE INVENTION

In order to attain the objectives that they had set themselves, the inventors have had to find solutions to the various problems listed above and to apply them simultaneously to a single form, since, in order to counter the main methods of misuse, the pharmaceutical form must be both difficult to crush and its AP must be difficult to extract in various solvents and in various volumes.

The pharmaceutical form according to the invention uses harmless and economical physicochemical means (these are compounds which are pharmacologically neutral, approved as excipients by the various pharmacopoeae and registration authorities).

One objective of the present invention is to provide a novel multimicroparticulate form which has the ability to resist dose dumping when it is placed in a large volume of alcohol; furthermore, this form is capable of resisting attempts at intentional misuse (crushing, extraction for injection). The approach which was selected to measure the resistance of the MR pharmaceutical forms to an alcohol-induced dose dumping consists in modifying the conventional tests for dissolution of MR pharmaceutical forms by introducing ethanol into the dissolution medium, for example at a concentration of 10% or of 40% (v/v). The order of magnitude of the final volume is 50 to 900 ml. For a certain number of MR pharmaceutical forms, it is observed that coadministration of said form with alcoholic beverages would lead to an undesired acceleration of the release of the AP(s).

The profile of the desired pharmaceutical form must be adapted to the specifications and depends on the coating of the microparticles. In doing this, it is necessary to avoid ending up with undesired types of behavior, such as:

-   -   dissolution profiles which are not controllable, in particular         the profile is no longer completely controlled by the coating of         the microparticles;     -   loss of the anti-crushing properties of the microparticles of         AP;     -   dose dumping in the presence of alcohol.

It is to the applicant's credit to have discovered that it is possible, through a judicious choice of excipients, of the proportions thereof and of the methods of using them, to obtain a formulation which corresponds as well as possible to the specifications of the present application.

In other words, the inventors have been able to reconcile the properties conferred by excipients of different nature, in order to obtain, through a judicious choice of the nature of each of these excipients (coating excipient, viscosity modifying excipient, quenching excipient, etc.), of their location (in a microparticle, a binder, a granule, etc.) and of their content, a formulation which corresponds to the initial specifications.

More specifically, the present invention is directed toward an oral pharmaceutical form comprising microparticles of reservoir type, with modified release of at least one AP, not subject to dose dumping in the presence of alcohol, i.e. which resists immediate AP, dose dumping in the presence of alcohol, in particular in a large volume and, in addition, the composition and the structure of which make it possible to prevent misuse of the AP this form contains, especially due to anti-misuse means. In particular, the anti-misuse means comprise at least anti-crushing means.

In this pharmaceutical form according to the invention:

-   -   the means which prevent AP dose dumping in the presence of         alcohol comprise at least one agent D which is a         pharmaceutically acceptable compound, the rate of hydration or         of solvation or the ability to hydrate or to solvate of which is         greater in an aqueous medium free of alcohol than in an         alcoholic solution; and     -   at least part of the AP is contained in coated microparticles         comprising a coating layer R which ensures the modified release         of the AP and which, simultaneously, confers, on the coated         microparticles of AP, resistance to crushing, so as to prevent         misuse;     -   and, optionally, at least one viscosity agent V;     -   and, optionally, at least one quenching agent Q.

In particular, with the oral pharmaceutical form according to the invention, the time for release of 50% of the AP, in an alcoholic solution, is not decreased by more than three-fold compared with the time for release of 50% of the AP measured in an aqueous medium free of alcohol.

The present invention is also directed toward a method for obtaining an oral solid pharmaceutical form which is anti-misuse by crushing and alcoholic extraction.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1: dissolution of the microparticles prepared in example 3

-   -   ▪: intact □: crushed

FIG. 2: dissolution of the gelatin capsules prepared in example 4

-   -   □: in 40% EtOH ▪: in 0.1N HCl

FIG. 3: dissolution of the tablets prepared in example 6

-   -   □: in 40% EtOH ▪: in 0.1N HCl

FIG. 4: dissolution of the tablets prepared in example 8

-   -   ▪: in 0.1N HCl Δ: in 0.1N HCl/EtOH (90/10 v/v)

FIG. 5: dissolution of the tablets prepared in example 9

-   -   ▪: in 0.1N HCl Δ: in 0.1N HCl/EtOH (90/10 v/v)

FIG. 6: dissolution of the tablets prepared in example 10

-   -   ▪: in 0.1N HCl □: in 0.1N HCl/EtOH (60/40 v/v)

FIG. 7: dissolution of the tablets prepared in example 12

-   -   ▴: in 0.1N HCl □: in 0.1N HCl/EtOH (80/20 v/v)         EtOH denotes ethanol.

DETAILED DESCRIPTION OF THE INVENTION

The oral pharmaceutical form according to the invention has anti-misuse properties; it comprises microparticles of reservoir type and allows modified release of the AP both in aqueous dissolution media and in alcoholic solutions.

Coated Microparticles of AP

The modified-release coated microparticles of AP are microparticles which are each coated with at least one coating (comprising, for example, at least one polymer) deposited according to the techniques known to those skilled in the art. In this respect, the reference Buri, et al.: Formes Pharmaceutiques Nouvelles, Lavoisier 1985, p. 175-227 already mentioned will, for example, be consulted.

The pharmaceutical form according to the invention is multimicroparticulate; it comprises, inter alia, reservoir microparticles with a core comprising the AP coated or film-coated with a coating. This AP core, or microparticle of AP, may be:

-   -   crude (pure) AP in pulverulent form, and/or     -   a matrix granule of AP mixed with various other ingredients,         and/or     -   a supported granule, such as a neutral support, for example of         cellulose or of sugar, coated with at least one layer containing         AP.

In the case of a matrix granule, the matrix contains the AP and, optionally, other pharmaceutically acceptable excipients, such as binders; surfactants, disintegrating agents, fillers, or pH controllers or modifiers (buffers).

In the case of a supported granule, the layer which contains the AP optionally contains other pharmaceutically acceptable excipients, such as binders, surfactants, disintegrating agents, fillers, or pH controllers or modifiers (buffers). The neutral support can be composed of sucrose and/or of saccharose and/or of dextrose and/or of lactose and/or of a sucrose/starch mixture. The neutral support can also be a cellulose microsphere or any other particle of pharmaceutically acceptable excipient. By way of nonlimiting example of a neutral support, mention may be made of particles of xanthan gum, of guar gum, of calcium phosphate or of calcium carbonate.

Advantageously, the neutral support has a mean diameter of between 1 and 800 μm, and preferably of between 20 and 500 μm.

Coating of the Microparticles of AP

Advantageously, the coated microparticles of AP comprise at least one coating layer R, better still a single coating layer R, which ensures the modified release of the AP and which, simultaneously, confers resistance to crushing on the coated microparticles of AP, in order to prevent misuse.

Even more preferentially, the coating layer R is designed in such a way that it makes it possible, in the event of crushing, to maintain a non-immediate (i.e. modified) release for at least part of the coated microparticles with modified release of AP.

The crushing envisioned here may, for example, be any crushing carried out according to the techniques normally used by perpetrators of misuse, i.e., in particular: pestle/mortar, coffee grinder, crushing between two spoons, biting/chewing, etc.

According to one advantageous embodiment, the coating R is designed in such a way that it makes it possible, in the event of crushing, to maintain a modified release for at least 40%, preferably at least 60%, and even more preferentially at least 80%, of the coated microparticles for modified release of AP.

Preferably, the anti-crushing coating layer R comprises:

-   -   at least one film-forming (co)polymer A1 which is insoluble in         the fluids of the digestive tube;     -   at least one (co)polymer A2 which is soluble in the fluids of         the digestive tube;     -   at least one plasticizer A3;     -   optionally, at least one surfactant and/or one lubricant and/or         one mineral filler and/or one organic filler A4.

In accordance with a purely illustrative and nonlimiting oriented selection of the invention:

-   -   A1 is chosen from the group comprising:         -   water-insoluble derivatives of cellulose, preferably             ethylcellulose and/or cellulose acetate,         -   acrylic polymers, for example copolymers of (meth)acrylic             acid and of alkyl (for example, methyl) ester, copolymers of             an ester of acrylic acid and methacrylic acid bearing at             least one quaternary ammonium group (preferably at least one             copolymer of alkyl (meth)acrylate and of             trimethylammonioethyl methacrylate chloride) and, more             specifically, the products sold under the trademarks             Eudragit® RS and/or Eudragit® RL,         -   poly(vinyl acetate)s,         -   and mixtures thereof;     -   A2 is chosen from the group comprising:         -   nitrogenous (co)polymers, preferably from the group             comprising polyacrylamides, poly-N-vinylamides,             polyvinylpyrrolidones (PVPs) and poly-N-vinyllactams,         -   water-soluble derivatives of cellulose,         -   polyvinyl alcohols (PVAs),         -   polyalkylene oxides, preferably polyethylene oxides (PEOs),         -   polyethylene glycols (PEGs),         -   and mixtures thereof;

PVP being particularly preferred;

-   -   A3 is chosen from the group comprising:         -   cetyl alcohol esters,         -   glycerol and esters thereof, preferably from the following             subgroup: acetylated glycerides, glyceryl monostearate,             glyceryl triacetate, glyceryl tributyrate,         -   phthalates, preferably from the following subgroup:             dibutylphthalate, diethylphthalate, dimethylphthalate,             dioctylphthalate,         -   citrates, preferably from the following subgroup: acetyl             tributyl citrate, acetyl triethyl citrate, tributyl citrate,             triethyl citrate,         -   sebacates, preferably from the following subgroup: diethyl             sebacate, dibutyl sebacate,         -   adipates,         -   azelates,         -   benzoates,         -   plant oils,         -   fumarates, preferably diethyl fumarate,         -   malates, preferably diethyl malate,         -   oxalates, preferably diethyl oxalate,         -   succinates, preferably dibutyl succinate,         -   butyrates,         -   cetyl alcohol esters,         -   malonates, preferably diethyl malonate,         -   castor oil (the latter being particularly preferred),         -   and mixtures thereof;     -   A4 is chosen from the group comprising:         -   anionic surfactants, preferably from the subgroup of alkali             metal or alkaline earth metal salts of fatty acids, stearic             acid and/or oleic acid being preferred,         -   and/or nonionic surfactants, preferably from the subgroup of             polyoxyethylenated oils, preferably polyoxyethylenated             hydrogenated castor oil,         -   polyoxyethylene/polyoxypropylene copolymers (poloxamer),         -   polyoxyethylenated sorbitan esters,         -   polysorbates,         -   polyoxyethylenated castor oil derivatives,         -   stearates, preferably calcium stearate, magnesium stearate,             aluminum stearate or zinc stearate,         -   stearyl fumarates, preferably sodium stearyl fumarate,         -   glycerol behenates,         -   talc,         -   colloidal silica,         -   titanium oxide, magnesium oxide,         -   bentonite,         -   microcrystalline cellulose,         -   kaolin,         -   aluminum silicate,         -   and mixtures thereof.

According to a preferred variant of the invention, the coating layer R contains the following components:

-   -   A1 is chosen from the group comprising water-insoluble         derivatives of cellulose, preferably ethylcellulose and/or         cellulose acetate,     -   A2 is chosen from the group comprising:         -   nitrogenous (co)polymers, preferably from the group             comprising polyacrylamides, poly-N-vinylamides,             polyvinylpyrrolidones (PVPs) and poly-N-vinyllactams,         -   water-soluble derivatives of cellulose,         -   polyethylene glycols (PEGS),         -   and mixtures thereof;     -   A3 is chosen from the group comprising: triethyl citrate,         dibutyl sebacate, plant oils, castor oil and mixtures thereof;     -   A4 is chosen from the group comprising: nonionic surfactants,         preferably from the following subgroup:         -   polyoxyethylenated oils, preferably polyoxyethylenated             hydrogenated castor oil,         -   polyoxyethylene/polyoxypropylene copolymers (poloxamer),         -   polyoxyethylenated sorbitan esters,         -   polysorbates,         -   stearates, preferably magnesium stearate,         -   and mixtures thereof.

Advantageously, for each constituent A1, A2, A3 and A4 of the coating layer R, its mass m (as % of the total mass A1+A2+A3+A4) bears out

for A1: 10≦m≦90, preferably 15≦m≦80, and more preferentially 60≦m≦80; for A2: 2≦m≦50, preferably 3≦m≦40, and more preferentially 5≦m≦25; for A3: 1≦m≦30, preferably 2≦m≦20, and more preferentially 5≦m≦15; for A4: 0≦m≦40, preferably 0≦m≦30, and more preferentially 0≦m≦20.

Relative to the total mass of the coated microparticles of AP, the coating layer R represents a fraction by mass Tp, expressed as % by weight on a dry basis, such that: Tp≧15; preferably between 30 and 60, and more preferentially between 40 and 60, and better still between 45 and 55, or approximately 50.

Preferably, the coated microparticles of AP have a volume-average diameter of less than or equal to 1000 μm, preferably of between 50 and 800 μm, and more preferably of between 100 and 600 μm, and better still of between 100 and 400 μm. The diameter of the microparticles is, unless otherwise mentioned, a volume-average diameter.

The techniques used for the manufacture of the microparticles of AP are conventional techniques such as, for example, the fluidized air bed spray coating technique, wet granulation, compacting, extrusion-spheronization.

Agent D

The pharmaceutical form according to the invention comprises at least one agent D which is a pharmaceutically acceptable compound, the rate of hydration or of solvation or the ability to hydrate or to solvate of which is greater in an aqueous medium free of alcohol than in an alcoholic solution. It may be:

-   -   a composition with a higher solubilization rate in water than in         an alcoholic solution;     -   a compound which is soluble in water and insoluble in an         alcoholic solution;     -   or a compound which is insoluble in water or in an alcoholic         solution, and which swells more or more rapidly in water than in         an alcoholic solution.

Preferably, the agent D is chosen from the group of following products:

-   -   cellulose derivatives such as, for example:         -   methylcellulose,         -   (hydroxy)(alkyl)celluloses, (for example,             hydroxypropylcellulose, hydroxypropylmethylcellulose,             hydroxyethylcellulose),         -   carboxyalkylcelluloses (for example, carboxymethylcellulose)             and salts thereof,         -   celluloses (powder or microcrystalline),         -   crosslinked carboxyalkylcelluloses:     -   crosslinked carboxymethylcelluloses (for example, sodium         croscarmellose),     -   polyalkylene oxides (for example, polyethylene oxide or         polypropylene oxide),     -   polysaccharides, for example:         -   natural starches (for example, of maize, wheat or potato) or             modified starches (for example, modified with sodium             glycolate),         -   alginates and salts thereof such as sodium alginate,         -   polacrilin potassium,         -   guar gums,         -   carrageenans,         -   pullulans,         -   pectins,         -   chitosans and derivatives thereof,         -   and mixtures thereof,     -   proteins, for example:         -   gelatin,         -   albumins,         -   casein,         -   lactoglobulins,         -   and mixtures thereof,     -   clays, such as bentonite, laponite and mixtures thereof.

Even more preferably, the agent D is chosen from the group of following products:

-   -   hydroxyalkylcelluloses (for example, hydroxypropylcellulose,         hydroxypropylmethylcellulose, hydroxyethylcellulose),     -   methylcellulose,     -   carboxy(alkyl)celluloses and salts thereof,     -   guar gums,     -   carrageenans,         and mixtures thereof.

The agent D can be incorporated in various ways, optionally combined with one another, into the pharmaceutical form according to the invention. It may be one of the constituents:

-   -   of the core of AP (or uncoated microparticle of AP):         -   in the neutral support of the microparticles and/or         -   in the layer containing the AP and deposited onto the             neutral support of the microparticles and/or         -   in the granule containing the AP; and/or     -   of the coating of the microparticles; and/or     -   of a mixture with the microparticles:         -   either in the binding phase of granules, pellets, tablets             including the microparticles of AP and/or         -   or in a different type of microparticles and/or         -   or in a different type of granules; and/or     -   one of the outer constituents of a monolithic form (for example,         constituent of a gelatin capsule, coating of a tablet or of a         gelatin capsule).

According to a first embodiment of the invention, the agent D is present in the core of AP, or uncoated microparticle of AP. Preferably, the agent D is present in the core of the microparticles in a proportion of 5% to 70%, preferably of 15% to 60%, of the total mass of the core of AP.

According to a second embodiment of the invention, the agent D is included in the coating of the microparticles. In this case, the agent D can constitute, on its own, a coating layer inside or outside the coating controlling the diffusion. It can also be mixed with the constituents A1, A2, A3 and, optionally, A4 of the coating which controls the modified release of the AP. Preferably, the agent D is present in the coating in a proportion of 3% to 30%, preferably of 10% to 20%, of the total mass of the coating. Preferably, the following compounds are chosen: the polymer A1 is ethylcellulose, the polymer A2 is PVP, the plasticizer A3 is castor oil, A4 is a poloxamer, and the agent D is chosen from guar gum, hydroxyethylcellulose, methylcellulose, hydroxypropylmethylcellulose and sodium carboxymethylcellulose, and mixtures thereof.

According to a third embodiment, the agent D is included in the binding phase of granules or of pellets or else of tablets including the microparticles of AP. The granules, pellets or tablets are obtained by the techniques known to those skilled in the art, such as, for example, granulation, extrusion or compression. The agent D is present as a mixture with the microparticles, in a proportion of 0.5% to 30% w/w, preferably of 0.5% to 25% w/w, and even more preferentially of 1% to 20% w/w, of the total mass of the mixture.

According to a fourth embodiment, the agent D is at least partly in the form of microparticles or, preferably, of granules distinct from those which contain the AP. For example, the coated microparticles of AP are granulated according to conventional techniques, and granules of the same size and of the same density, of agent D, are prepared separately, which granules can also contain a viscosity agent and/or a quenching agent (see below).

According to a fifth embodiment, the agent D is one of the components of the material constituting the gelatin capsule which contains the microparticles.

According to a sixth embodiment, the agent D is included in a coating deposited onto the gelatin capsule containing the microparticles or onto the tablet containing the microparticles. For example, the gelatin capsule is gelatin-based, and the coating contains sodium carboxymethylcellulose and/or hydroxyethylcellulose as agent D, preferably in a proportion of 25% w/w of agent D relative to the mass of the empty gelatin capsules.

In the case of the fifth and sixth embodiments, a finishing layer may be deposited onto the gelatin capsule or the tablet.

The various embodiments, as regards the agent D, can be combined with one another. In such a case, it is entirely possible to envision incorporating various agents D for each of the embodiments indicated.

Viscosity Agent V

The viscosity agent V is chosen from viscosity agents which are soluble in at least one of the following solvents: water, alcohols, ketones, and mixtures thereof, this or these agent(s) being capable of increasing the viscosity of the extraction solvent so as to counteract misuse, in particular by injection. The term “water” is here intended to mean any aqueous solvent, such as water, stricto sensu, or any aqueous solution, for example of organic acid (for example, acetic acid), saline solutions, sodas or beverages. The term “alcohols” is here intended to mean all alcohols taken by themselves or as a mixture with one another, and the term “ketones” is intended to mean all ketones taken by themselves or as a mixture with one another.

Preferably, the viscosity agent V is chosen from the following groups of polymers:

-   -   poly(meth)acrylic acids and derivatives thereof, and/or     -   polyalkylene glycols (for example, polyethylene glycol), and/or     -   polyalkylene oxides (for example, polyethylene oxide), and/or     -   polyvinylpyrrolidones, and/or     -   gelatins, and/or     -   polysaccharides, preferably from the subgroup comprising: sodium         alginate, pectins, guars, xanthans, carrageenans, gellans and         cellulose derivatives (in particular,         hydroxypropylmethylcellulose, methylcellulose,         hydroxyethylcellulose, hydroxypropylcellulose,         carboxymethylcellulose),     -   and mixtures thereof.

Advantageously, according to a preferred variant of the invention, the viscosity agent V is chosen from:

-   -   polyalkylene oxides (for example, polyethylene oxide), and/or     -   xanthans, and/or     -   cellulose derivatives (in particular, hydroxypropylcellulose),     -   and mixtures thereof.

According to one mode of the invention, the viscosity agent V is a polyethylene oxide having a high molecular weight, for example having a molecular weight of 1 million g/mol to 8 million g/mol, for example 2 million, 5 million or 7 million g/mol.

According to a preferred mode, the viscosity agent V is capable of increasing the viscosity of the liquid used for the possible extraction, so as to trap the AP extracted in the viscous medium. This agent V makes it possible to increase the viscosity of the extraction liquid, for example above 100 mPa·s, preferably 200 mPa·s, and even more preferentially above 500 mPa·s, and better still 1000 mPa·s.

According to one variant of the invention, the viscosity agent V is effective in the case of both an extraction in an aqueous phase or an organic phase; for example, the agent V is a mixture of hydrophilic and hydrophobic compounds, so as to ensure a high viscosity of the extraction liquid (for example ≧100 mPa·s), whether the latter is aqueous or organic.

The amount of agent V is adjusted so as to render the viscosity of 2.5 ml of extraction liquid greater than or equal to 100 mPa·s.

According to several variants, in the pharmaceutical form according to the invention, at least one viscosity agent V is present:

-   -   in and/or on microparticles,     -   and/or in the free state, i.e. not contained in, or supported         by, microparticles.

Advantageously, the viscosity agent is mainly in the form of microparticles distinct from the microparticles of AP. When the pharmaceutical form is a divided form (gelatin capsule, sachet, suspension to be reconstituted), the microparticles of viscosity agent have a density and a particle size comparable to those of the microparticles of AP. For example, the microparticles of viscosity agent V and the microparticles of AP have a similar size distribution and a similar density. Thus, they cannot be separated from the microparticles of AP, in particular by conventional means such as sifting or centrifugation.

When the pharmaceutical form according to the invention comprises granules containing, firstly, microparticles of AP and, secondly, granules containing viscosity agent V, optionally combined with the agent D, it is preferable for said granules to have a similar size distribution, a similar density, a similar shape and a similar color. Thus, the granules comprising the viscosity agent and/or the agent D are physically indistinguishable from the granules of AP, in order to obstruct the sorting thereof by any appropriate physical means.

Quenching Agent Q

When the multimicroparticulate pharmaceutical form comprises at least one salt of an active principle, or an active principle bearing a function ionizable in solution, a preferred embodiment of the invention consists in adding to said pharmaceutical form at least one quenching agent Q. The latter is chosen such that, during an attempt at extraction, it forms, with the AP, in an aqueous or aqueous-alcoholic solution, a poorly soluble complex.

For the purpose of the present invention, a quenching agent Q is an agent present in the pharmaceutical form in a free form, i.e. a noncomplexed form. The term “noncomplexed” signifies that there is no complex or chemical interaction between the quenching agent Q and the salt of active principle AP in the solid pharmaceutical form.

When the salt of AP and the quenching agent Q are simultaneously in a solvent, for example in the case of an illicit attempt to extract the AP, the quenching agent Q is capable of inducing a complexation or a chemical interaction with the salt of AP in said solvent. For the purpose of the present invention, the quenching agent Q is considered to be “capable of inducing a complexation” with the salt of AP when the quenching agent Q is capable of inducing complexation of the salt of AP in at least one usual solvent chosen from water and aqueous solutions, such as water-ethanol mixtures, alcohol, alcoholic beverages, sodas, vinegar, aqueous hydrogen peroxide solution, and mixtures thereof. Advantageously, the quenching agent Q is capable of inducing complexation of the salt of AP in more than one of these usual solvents.

The quenching agents Q used to trap the AP, in particular analgesic, are harmless, including for a regular use. These are pharmacologically inert products approved by the various pharmacopoeae and authorities for registering drugs.

In one pharmaceutical form according to the invention, at least one quenching agent Q is present:

-   -   in microparticles free of AP, and/or     -   on microparticles, and/or     -   in the free state, i.e. not contained in, or supported by,         microparticles.

Preferably, in a pharmaceutical form according to the invention, the quenching agent Q is present in a first phase separate from at least a second phase, said second phase containing at least one salt of AP. For example, the pharmaceutical form comprises microparticles of salt of AP and microparticles of quenching agent Q which are distinct. Advantageously, said microparticles have a similar size distribution and a similar density, and are impossible to separate from one another by sifting.

Preferably, the quenching agent Q comprises a salt, which contains ions capable of forming a complex with the AP in solution. These ions are preferably organic ions of polarity opposite to that of the AP in solution: if, in solution, the AP is in anionic form, the quenching agent Q comprises an organic cation, a metal cation, or a mixture thereof. Similarly, when the AP in solution is in cationic form, the quenching agent Q comprises an organic anion.

For example, mention may be made of the following salts which have an organic anion:

-   -   anionic organic salts, such as sodium dodecyl sulfate or sodium         docusate;     -   anionic polymers, such as (meth)acrylic copolymers (for example,         Eudragit© S and Eudragit® L), crosslinked polyacrylic acids (for         example, Carbopol), carboxymethylcellulose and its derivatives,         crosslinked carboxymethylcellulose and its derivatives and other         polysaccharides (for example, alginate, xanthan gum or gum         arabic), alginate (sulfonate) propylene glycol;     -   monovalent or polyvalent salts, such as glucuronates, citrates,         acetates, carbonates, gluconates, succinates, phosphates,         glycerophosphates, lactates, trisilicates, fumarates, adipates,         benzoates, salicylates, tartrates, sulfonamides, acesulfames;     -   saponified fatty acids, such as salts of acetic acid, succinic         acid, citric acid, stearic acid, palmitic acid, and         self-emulsifying glyceryl monooleates;     -   polyamino acids, proteins or peptides, such as albumins,         caseins, globulins and enzymes;     -   and mixtures thereof.

In another embodiment, the ion of polarity opposite to that of the AP in solution is a metal cation, an organic cation, or a mixture thereof: For example, mention will be made of the following salts which contain an organic or metal cation:

-   -   cationic salts, for example of the metals Ca, Fe, Mg or Zn, in         the form of acesulfames, acetates, adipates, benzoates,         carbonates, chlorides, citrates, fluorides, fumarates,         gluconates, glucuronates, glycerophosphates, hydroxides,         iodates, iodides, lactates, oxides, phosphates, trisilicates,         phosphates, salicylates, succinates, sulfonamides, tartrates;     -   organic cationic salts, such as quaternary ammonium salts, in         particular trimethyltetradecylammonium bromide or benzethonium         chloride;     -   cationic polymers, such as chitosan and (meth)acrylic copolymers         (for example, Eudragit® RS, Eudragit® RL or Eudragit® E);     -   polyamino acids, proteins or peptides;     -   and mixtures thereof.

The quenching agent Q may be an ion exchange resin, preferably a strongly acidic cation exchange resin when the AP is cationic or a strongly basic anion exchange resin when the AP is anionic. Advantageously, such an ion exchange resin is contained in a first phase distinct from a second phase which contains the AP.

In one embodiment of the invention, the ion exchange resin will, for example, be a derivative of a styrene/divinylbenzene copolymer.

In one embodiment of the invention, the strongly acidic cation exchange resin will, for example, be a derivative of a sulfonic styrene/divinylbenzene copolymer, such as Amberlite® IRP69, Amberlite® IR69F (Rohm and Haas); Amberlite 200, Amberlite 200C (Rohm and Haas), or Dowex 88 (Dow), and the like.

In one embodiment of the invention, the strongly basic anion exchange resin will, for example, be chosen from derivatives of styrene/divinylbenzene copolymers bearing quaternary ammonium functions, such as Duolite® AP143 (Rohm and Haas), Amberlite IRA958, Amberlite IRP67 (Rohm and Haas) and Dowex 22 (Dow).

The quenching agent Q in the form of resin can also be chosen from crosslinked copolymers of methacrylic acid and of divinylbenzene or a salt thereof, such as Amberlite® IRP88 and Amberlite® IRP64 (Rohm and Haas), and Dowex MAC-3 (Dow).

The quenching agent Q in the form of ion exchange resin can also be chosen from phenolic polyamines, such as Amberlite® IRP58 (Rohm and Haas).

Mixtures of these various resins can also be envisioned.

According to one embodiment of the invention, the quenching agent Q in the form of ion exchange resin is in a first phase separate from at least a second phase, said second phase comprising the salt of AP. For example, the quenching agent Q in the form of ion exchange resin is contained in microparticles distinct from the microparticles comprising the salt of AP. The microparticles of AP and the microparticles of quenching agent Q in the form of ion exchange resin can be in a form such that they have a similar size distribution and a similar density and such that they cannot be separated by sifting.

In a first preferred embodiment of the invention, the quenching agent Q is chosen from:

-   -   anionic organic salts, such as sodium dodecyl sulfate or sodium         docusate;     -   cationic organic salts, such as quaternary ammonium salts, in         particular trimethyltetradecylammonium bromide or benzethonium         chloride;     -   strongly acidic cation exchange resins or strongly basic anion         exchange resins, depending on the polarity of the AP.

In a second preferred embodiment of the invention, the quenching agent Q is chosen from:

-   -   strongly acidic cation exchange resins: Amberlite® IRP69,         Amberlite® IR69F (Rohm and Haas); Amberlite® 200, Amberlite®         200C (Rohm and Haas), or Dowex® 88 (Dow), and mixtures thereof,         when the AP is cationic;     -   strongly basic anion exchange resins: Duolite® AP143 (Rohm and         Haas), Amberlite® IRA958, Amberlite® IRP67 (Rohm and Haas), and         Dowex® 22 (Dow), and mixtures thereof, when the AP is anionic.

The amount of agent Q is adjusted by those skilled in the art by calculating the amount of ionic charge required to trap all or part of the dose of AP contained in the unit form. The amount of quenching agent Q must be such that it makes it possible to complex sufficient AP so that the remaining amount of AP free in solution is insufficient to achieve the desired effect, in the case of illicit use. Preferably, the amount of quenching agent Q is sufficient to complex all the AP of the unit dose.

Excipient in the Free State

The pharmaceutical form can optionally contain one or more pharmaceutically acceptable excipients, in the free state, i.e. not contained in or supported by microparticles of AP, said excipient contributing to the resistance of the coated microparticles of AP to crushing.

Preferably, these excipients which contribute to the resistance to crushing of the coated microparticles of AP are chosen from the group comprising:

-   -   calcium stearate;     -   glyceryl palmitostearate;     -   magnesium oxide;     -   polyalkylene glycols, for example polyethylene glycols;     -   polyvinyl alcohol;     -   sodium benzoate;     -   stearic acid;     -   corn starch;     -   talc;     -   colloidal silica;     -   zinc/magnesium stearate;     -   stearyl fumarate;     -   and mixtures thereof.

Description of the Pharmaceutical Form

Preferably, with the oral pharmaceutical form according to the invention, for modified release of at least one AP both in aqueous dissolution media and in alcoholic solutions, the time for release of 50% of the AP in an alcoholic solution:

-   -   is not decreased by more than three-fold compared with the time         for release of 50% of the AP measured in an aqueous medium free         of alcohol;     -   is preferably not decreased by more than two-fold compared with         the time for release of 50% of the AP measured in an aqueous         medium free of alcohol;     -   is preferably not decreased by more than 1.5-fold compared with         the time for release of 50% of the AP measured in an aqueous         medium free of alcohol;     -   is preferably similar to that measured in an aqueous medium,         according to the similarity factor f₂ defined above;     -   or even the time for release of 50% of the AP in an alcoholic         solution is greater than the time for release of 50% of the AP         in an aqueous medium free of alcohol.

In general, the pharmaceutical form according to the invention comprises:

-   a) an AP, at least part of which is contained in microparticles     individually coated with a coating R which ensures the modified     release of the AP and simultaneously confers resistance to crushing     of the coated microparticles of AP. The constituents A1, A2, A3 and     A4 of the coating layer R meet, in terms of percentage by mass     relative to the total mass A1+A2+A3+A4, the requirements mentioned     above; -   b) at least one agent D which is present in a proportion of 0.5% to     30% w/w, preferably of 0.5% to 25% w/w, and even more preferentially     of 1% to 20% w/w, of the total mass of the unit form; -   c) optionally, at least one viscosity agent V present in a     proportion of 2 to 400 mg, preferably of 5 to 200 mg, and even more     preferentially of 10 to 100 mg per unit form; -   d) optionally, at least one quenching agent Q, the amount of which     is adjusted in order to trap all or part of the dose of AP contained     in the unit form.

According to a preferred mode, the quenching agent Q is included in a phase or in microparticles separate from the microparticles of AP.

Preferably, the viscosity agent V is contained in microparticles distinct from the microparticles of AP. Advantageously, the pharmaceutical form according to the invention comprises microparticles of viscosity agent V and microparticles of AP, said microparticles having a similar size distribution and a similar density and being impossible to separate from one another by sifting.

According to an embodiment 1 of the invention, the coating layer R contains the following components:

-   -   A1 is chosen from the group comprising water-insoluble         derivatives of cellulose, preferably ethylcellulose and/or         cellulose acetate,     -   A2 is chosen from the group comprising:         -   nitrogenous (co)polymers, preferably from the group             comprising polyacrylamides, poly-N-vinylamides,             polyvinylpyrrolidones (PVPs) and poly-N-vinyllactams,         -   water-soluble derivatives of cellulose,         -   polyethylene glycols (PEGs),         -   and mixtures thereof;     -   A3 is chosen from the group comprising: triethyl citrate,         dibutyl sebacate, plant oils, castor oil, and mixtures thereof;     -   A4 is chosen from the group comprising: nonionic surfactants,         preferably from the following subgroup:         -   polyoxyethylenated oils, preferably polyoxyethylenated             hydrogenated castor oil, oxide         -   polyethylene oxide-polypropylene copolymers (poloxamer),         -   polyoxyethylenated sorbitan esters,         -   polysorbates,         -   stearates, preferably magnesium stearate,         -   and mixtures thereof.

According to an embodiment 2 of the invention, the agent D is chosen from the group of following products:

-   -   hydroxyalkylcelluloses (for example, hydroxypropylcellulose,         hydroxypropylmethylcellulose, hydroxyethylcellulose),     -   methylcellulose,     -   carboxy(alkyl)celluloses, and salts thereof,     -   guar gums,     -   carrageenans,     -   and mixtures thereof.

According to an embodiment 3 of the invention, the viscosity agent V is chosen from:

-   -   polyalkylene oxides (for example, polyethylene oxide), and/or     -   xanthans, and/or     -   cellulose derivatives (in particular, hydroxypropylcellulose),     -   and mixtures thereof.

According to a variant of embodiment 3 of the invention, the viscosity agent V is a polyethylene oxide having a high molecular weight, for example having a molecular weight of 1 million g/mol to 8 million g/mol, for example 2 million, 5 million or 7 million g/mol.

According to an embodiment 4 of the invention, the quenching agent Q is chosen from:

-   -   anionic organic salts, such as sodium dodecyl sulfate or sodium         docusate;     -   cationic organic salts, such as quaternary ammonium salts, in         particular trimethyltetradecylammonium bromide or benzethonium         chloride;     -   ion exchange resins, preferably a strongly acidic cation         exchange resin or a strongly basic anion exchange resin.

According to an embodiment 5 of the invention, the quenching agent Q is chosen from:

-   -   strongly acidic cation exchange resins: Amberlite® IRP69,         Amberlite® IR69F (Rohm and Haas); Amberlite 200, Amberlite 200C         (Rohm and Haas), or Dowex 88 (Dow), and mixtures thereof, when         the AP is cationic;     -   strongly basic anion exchange resins: Duolite® AP143 (Rohm and         Haas), Amberlite IRA958, Amberlite IRP67 (Rohm and Haas) and         Dowex 22 (Dow), and mixtures thereof, when the AP is anionic.

These embodiments 1 to 5 of the invention can be combined with one another. In particular, a pharmaceutical form according to the invention simultaneously comprises the coating layer R and the agent D of embodiments 1 and 2. According to a preferred variant, the pharmaceutical form also comprises at least one viscosity agent V according to embodiment 3. Finally, the pharmaceutical form can contain a quenching agent Q according to embodiment 4 or 5.

Of course, the final pharmaceutical form according to the invention may be optimized by the addition of other conventional ingredients known to those skilled in the art, such as, in particular, colorants, pigments, preserving agents, aromas, and mixtures thereof.

According to a preferred embodiment 6, the unit pharmaceutical form according to the invention is a tablet, comprising:

-   -   a) an AP, at least part of which is contained in microparticles         individually coated with a coating R which ensures the modified         release of the AP and simultaneously confers resistance to         crushing of the coated microparticles of AP.

For each constituent A1, A2, A3 and A4 of the coating layer R, its mass m (as % of the total mass A1+A2+A3+A4) bears out:

for A1: 10≦m≦90, preferably 15≦m≦80, and more preferentially 60≦m≦80; for A2: 2≦m≦50, preferably 3≦m≦40, and more preferentially 5≦m≦25; for A3: 1≦m≦30, preferably 2≦m≦20, and more preferentially 5≦m≦15; for A4: 0≦m≦40, preferably 0≦m≦30, and more preferentially 0≦m≦20;

-   -   b) at least one agent D is present as a mixture with the         microparticles in a proportion of 1% to 30% w/w, preferably of         2% to 25% w/w, and even more preferentially of 2% to 20% w/w, of         the total mass of the unit form;     -   c) at least one viscosity agent V is contained in microparticles         distinct from the microparticles of AP. The viscosity agent V is         present in a proportion of 2 to 400 mg, preferably of 5 to 200         mg, and even more preferentially of 10 to 100 mg per unit form;     -   d) optionally, at least one quenching agent Q is contained in         microparticles distinct from the microparticles of AP and of         viscosity agent. The amount of agent Q is adjusted in order to         trap all or part of the dose of AP contained in the unit form;     -   e) and, optionally, compression excipients.

According to an embodiment 7 of the invention, the tablet of embodiment 6 comprises at least one quenching agent Q.

As regards embodiments 6 and 7 of the invention, reference may be made to embodiments 1 to 5 of the invention to determine the nature of the components A1, A2, A3 and A4 of the coating layer R, that of the agent D, that of the viscosity agent V and, optionally, that of the quenching agent Q.

According to a preferred embodiment 8, the unit pharmaceutical form according to the invention is a gelatin capsule comprising:

-   -   a) an AP, at least part of which is contained in microparticles         individually coated with a coating R which ensures the modified         release of the AP and simultaneously confers resistance to         crushing of the coated microparticles of AP.

For each constituent A1, A2, A3 and A4 of the coating layer R, its mass m (as % of the total mass A1+A2+A3+A4) bears out:

for A1: 10≦m≦90, preferably 15≦m≦80, and more preferentially 60≦m≦80; for A2: 2≦m≦50, preferably 3≦m≦40, and more preferentially 5≦m≦25; for A3: 1≦m≦30, preferably 2≦m≦20, and more preferentially 5≦m≦15; for A4: 0≦m≦40, preferably 0≦m≦30, and more preferentially 0≦m≦20;

-   -   b) at least one agent D which is present in a proportion of 0.5%         to 20% w/w, preferably of 0.5% to 15% w/w, and even more         preferentially of 1% to 10% w/w, of the total mass of the unit         form;     -   c) optionally, at least one viscosity agent V present in a         proportion of 2 to 400 mg, preferably of 5 to 200 mg, and even         more preferentially of 10 to 100 mg per unit form;     -   d) optionally, at least one quenching agent Q, the amount of         which is adjusted in order to trap all or part of the dose of AP         contained in the unit form.

According to an embodiment 9 of the invention, the gelatin capsule of embodiment 8 comprises at least one viscosity agent V.

According to an embodiment 10 of the invention, the gelatin capsule of embodiment 9 comprises at least one quenching agent Q.

Advantageously, the pharmaceutical form of gelatin capsule type comprises microparticles of viscosity agent V and/or microparticles of quenching agent Q, the microparticles of viscosity agent V and the microparticles of quenching agent Q being distinct from the microparticles of AP.

Preferably, the pharmaceutical form of gelatin capsule type comprises microparticles of AP, and also microparticles of viscosity agent V and/or microparticles of quenching agent Q, said microparticles having similar size distributions and similar densities and being impossible to separate from one another by sifting.

As regards embodiments 8, 9 and 10 of the invention, reference may be made to embodiments 1 to 5 of the invention to determine the nature of the components A1, A2, A3 and A4 of the coating layer R, that of the agent D, that of the viscosity agent V and, optionally, that of the quenching agent Q.

Active Principle

The AP used may belong, for example, to at least one of the families of following active substances: opiates, analgesics, antalgics, antitussives, anxiolytics, benzodiazepines, anorexigens, antidepressants, antiepileptics, antimigraine agents, antiparkinsonian agents, barbiturates, hypnotics, laxatives, neuroleptics, psychostimulants, psychotropic agents, sedatives, amphetamines, stimulants.

Even more specifically, the AP used is chosen from the following compounds: acetorphine, acetyl-alpha-methylfentanyl, acetyldihydrocodeine, acetylmethadol, alfentanil, allylprodine, alpha-cetylmethadol, alphameprodine, alphaprodine, alphamethadol, alpha-methylfentanyl, alpha-methylthiofentanyl, alphaprodine, anileridine, atropine, butorphanol, benzethidine, benzylmorphine, beta-hydroxyfentanyl, beta-hydroxymethyl-3-fentanyl, beta-cetylmethadol, betameprodine, betamethadol, betaprodine, bezitramide, buprenorphine, dioxaphetyl butyrate, clonitazene, cyclazocine, cannabis, cetobemidone, clonitazene, codeine, coca, cocaine, codoxime, dezocine, dimenoxadol, dioxaphetylbutyrate, dipipanone, desomorphine, dextromoramide, dextropropoxyphene, diampromide, diethylthiambutene, difenoxine, dihydrocodeine, dihydroetorphine, dihydromorphine, dimenoxadol, dimepheptanol, dimethylthiambutene, diphenoxylate, dipipanone, drotebanol, eptazocine, ethoheptazine, ethylmethylthiambutene, ethylmorphine, etonitazene, ecgonine, ephedrine, ethylmethylthiambutene, ethylmorphine, etonitazene, etorphine, etoxeridine, fentanyl, furethidine, heroin, hydrocodone, hydromorphinol, hydromorphone, hydroxypethidine, isomethadone, ketobemidone, levallorphan, lofentanil, levomethorphan, levomoramide, levophenacylmorphan, levorphanol, meptazinol, meperidine, metazocine, methadone, methyldesorphine, methyldihydromorphine, methylphenidate, methyl-3-thiofentanyl, methyl-3-fentanyl, metopon, moramide, morpheridine, morphine, myrophine, nalbuphine, narceine, nicomorphine, norlevorphanol, normethadone, nalorphine, normorphine, nicocodine, nicodicodine, nicomorphine, noracymethadol, norcodeine, norlevorphanol, normethadone, normorphine, norpipanone, opium, oxycodone, oxymorphone, papaveretum, phenadoxone, phenoperidine, promedol, properidine, propiram, propoxyphene, para-fluorofentanyl, pentazocine, pethidine, phenampromide, phenazocine, phenomorphan, phenoperidine, pholcodine, piminodine, piritramide, proheptazine, propranolol, properidine, propiram, racemethorphan, racemoramide, racemorphan, remifentanil, sufentanil, thebacone, thebaine, thiofentanyl, tilidine, trimeperidine, tramadol, and the pharmacologically acceptable salts, esters, hydrates, polymorphs and isomers thereof, and mixtures thereof.

Even more specifically, the analgesic AP used is selected from the group consisting of oxycodone hydrochloride, morphine sulfate, oxymorphone hydrochloride, hydromorphone hydrochloride, hydrocodone hydrochloride and tramadol hydrochloride.

For the purpose of the invention, the expression “pharmaceutical formulation” is understood in the broad sense, i.e. veterinary or dietetic formulations in particular are encompassed.

According to another of its aspects, the invention is directed toward a formulation which comprises a plurality of microparticles (of AP, coated or uncoated; optionally, of viscosity agent) as defined above, for example at least 500, preferably from 1000 to 1 000 000, and even more preferentially from 5000 to 500 000 microparticles.

According to another of its aspects, the invention is directed toward a pharmaceutical formulation comprising a plurality of populations of coated microparticles of AP, said populations differing from one another by virtue of their release kinetics and/or by virtue of the AP that they contain.

Advantageously, the pharmaceutical form according to the invention can comprise modified-release microparticles of AP and immediate-release microparticles of AP.

Without wishing to be limiting, it should nevertheless be underlined that the pharmaceutical formulation according to the invention is particularly advantageous in that it can be in the form of a single oral daily dose comprising from 500 to 500 000 microparticles, including the coated microparticles of AP.

Without it being limiting, the pharmaceutical formulation comprising coated microparticles according to the invention is in a pharmaceutical form chosen from the group comprising in particular: tablets (advantageously orodispersible or gastrodispersible), powders, suspensions, syrups, powders for suspensions to be reconstituted, or gelatin capsules.

It may be advantageous to mix, in the same gelatin capsule, the same tablet or the same powder, at least two types of coated microparticles of AP having different release kinetics but included in the characteristic scope of the invention.

According to one variant, the pharmaceutical form can also be a monolithic form (for example, tablet).

According to a first variant, the pharmaceutical form according to the invention cannot be converted easily into a dry form that can be administered by nasal aspiration and with immediate release of AP.

According to a second variant, the pharmaceutical form according to the invention cannot be converted into an injectable form with immediate release of AP.

According to a third variant, the pharmaceutical form according to the invention comprises modified-release AP and, optionally, immediate-release AP. This variant can be combined with the first and second variants mentioned above. This means that, in a pharmaceutical form which comprises modified-release AP and immediate-release AP, the modified-release AP cannot be converted into a dry form that can be administered by nasal aspiration or into an injectable form, and with immediate release.

A subject of the present invention is also the methods for obtaining the pharmaceutical forms according to the invention as defined above, said methods being divided up into several steps consisting essentially in:

-   a) preparing uncoated microparticles of AP by:     -   extrusion/spheronization of AP with, optionally, one or more         agent(s) D or pharmaceutically acceptable excipient(s), and/or;     -   wet granulation of AP with, optionally, one or more agent(s) D         or pharmaceutically acceptable excipient(s), and/or;     -   compacting of AP with, optionally, one or more agent(s) D or         pharmaceutically acceptable excipient(s), and/or;     -   spraying of AP, with, optionally, one or more agent(s) D or         pharmaceutically acceptable excipient(s), in a dispersion or in         a solution in an aqueous or organic solvent, onto a neutral         support or particles of agent D, and/or;     -   sifting of powder or crystals of AP; -   b) preparing reservoir microparticles of AP by:     -   spraying, in a fluidized air bed, of a solution or dispersion         containing one or more compounds A1, A2 and A3 and, optionally,         one or more compounds A4 and/or D, onto the microparticles of         AP; the microparticles of AP may have been coated beforehand         with one or more agents D; the coated microparticles of AP can         optionally be coated with one or more agents D; -   c) preparing the final form of the drug by:     -   granulation and/or extrusion/spheronization of the reservoir         microparticles of AP with agents D, V and Q for formulation in         gelatin capsules or sachets; or     -   mixing of reservoir microparticles of AP with, optionally, one         or more agent(s) D, V and Q and pharmaceutically acceptable         excipients, so as to obtain a tablet; this tablet can optionally         be coated in a coating drum with one or more layers containing         the agent D and/or pharmaceutically acceptable excipients; or     -   formulation in gelatin capsules, of reservoir microparticles of         AP, of V and of Q; the gelatin capsules can optionally be coated         in a drum or fluidized air bed with one or more agent(s) D         and/or pharmaceutically acceptable excipients; or     -   formulation in sachets, of reservoir microparticles of AP, of V         and of Q with, optionally, one or more agent(s) D and/or         pharmaceutically acceptable excipients.

The invention also relates to a method of treating pain, comprising the administration of a pharmaceutical form as described above, to a patient needing the latter.

The invention also relates to a method for preventing misuse of an active principle, in particular analgesic or opiate, comprising the use of a pharmaceutical form as described above.

The invention will be explained more clearly by the examples hereinafter, which are given only by way of illustration and make it possible to clearly understand the invention and to reveal the variants of preparation and/or of use thereof, and also the various advantages thereof.

EXAMPLES Example 1 Preparation According to the Invention of Anti-Crushing Microparticles of Oxycodone HCl

Granules:

1615 g of oxycodone HCl are added to a solution containing 85 g of Methocel E5 (hypromellose/Dow), 2052 g of demineralized water and 1105 g of ethanol. The mixture is stirred at 67° C. The solution is then sprayed, in a Glatt GPCG 1.1 fluidized air bed device, onto 300 g of particles of Xantural 180 (xanthan gum/Danisco) sifted between 50 and 180 μm. The product recovered is then sifted through 80-300 μm.

Microparticles:

495 g of the granules prepared above are then film-coated, in a Glatt GPCG 1.1 fluidized air bed device, with a solution containing 296 g of Ethocel 20 Premium (ethylcellulose/Dow), 24 g of Plasdone K29/32 (povidone/ISP), 49 g of Cremophor RH 40 (PEG 40-hydrogenated castor oil/BASF), 41 g of castor oil (Garbit huilerie), 2795 g of acetone and 1863 g of isopropanol.

The mass of the coating represents 45% of the total mass of the MR microparticle of oxycodone HCl.

Example 2 Pharmaceutical Form According to Unpublished Application FR0553437

55 g of microparticles prepared in Example 1 are mixed with 18 g of Polyox WSR303 (polyethylene oxide/Dow) sifted between 150 and 300 μm, 26 g of Amberlite IR69F (Rhom & Haas) crushed and sifted between 160 and 300 μm, 0.5 g of Aerdsil 200 (colloidal silica/Degussa) and 1 g of magnesium stearate.

405 mg of this mixture are introduced into gelatin capsules size 0.

This gelatin capsule is placed in a large volume (500 ml) of solution containing 40% of ethanol and the percentage released after stirring for 0.5 and 1 hour is measured:

Time Oxycodone (h) released (%) 0.5 19 1 60

These results show that, in the presence of a large amount of alcoholic solution, the amount of oxycodone released is relatively high after one hour. This may present a risk for the patient, which is why the applicant has sought to, develop a form with a slower release in the presence of alcohol.

Example 3 Crushing Test on the Microparticles of Oxycodone HCl

The microparticles prepared in Example 1 are lubricated with 1.0% of magnesium stearate and 0.5% of Aerosil.

These microparticles, in a proportion of 197 mg corresponding to a dose of 80 mg of oxycodone HCl, are introduced into a dissolutest, either as they are (INTACT), or highly crushed for 2 min by means of a pestle and mortar (CRUSHED).

The results of the dissolution test in 900 ml of 0.1N HCl (D as %) as a function of time (t in h) of the intact and crushed doses are reported in FIG. 1. The dissolution profiles are very similar, with a slightly more rapid release during the first minutes in the case of the crushed microparticles; subsequently, the profiles are similar.

Example 4 Preparation of Gelatin Capsules According to the Invention

Mixing:

55 g of microparticles prepared in Example 1 are mixed with 18 g of Polyox WSR303 (polyethylene oxide/Dow) sifted between 150 and 300 μm, 26 g of Amberlite IR69F (Rhom & Haas) crushed and sifted between 160 and 300 μm, 0.5 g of Aerosil 200 (colloidal silica/Degussa) and 1 g of magnesium stearate. The mixture is homogenized for 15 minutes.

Gelatin Capsules:

35 gelatin capsules size 0 (white/white) are each filled with 405 mg of the mixture above.

Coating of the Gelatin Capsules:

The gelatin capsules above are then coated with 16 mg per gelatin capsule of Blanose 7LF (sodium carboxymethylcellulose/Aqualon) dissolved beforehand at 6% (m/m) in demineralized water.

The dissolution tests in 900 ml of 0.1N HCl and (40% EtOH; 60% 0.1N HCl) are reported in FIG. 2. It is noted that, in an ethanolic solution, the dissolution kinetics are considerably slowed.

Example 5 Misuse Test on the Content of the Gelatin Capsule of Example 4

In the following misuse tests, the content of a gelatin capsule as described in Example 4 is first crushed by means of a pill crusher (LGS pill crusher) and then brought into contact with 10 ml of solvent and left stirring for 120 min at ambient temperature.

The mixture is then removed by means of an insulin syringe through a 0.45 μm filter. The amounts of oxycodone HCl recovered are analyzed by HPLC. The results of the extraction tests are reported in Table 1.

TABLE 1 Oxycodone Solvent extracted (%) 70% Isopropanol 0 Diethyl ether 0.02 Ethyl acetate 1.9 Ethanol 13.7 Acetone 1.1 Cooking oil <0.01

The amounts extracted are less than 15% of the dose.

Example 6 Preparation of Tablets According to the Invention

10 g of the microparticles of oxycodone prepared in Example 1, 5 g of Amberlite IR69F (Rhom & Haas) sifted between 160 and 300 μm, 2.5 g of Polyox WSR 303, 10 g of Avicel PH 101 (microcrystalline cellulose/FMC), 5 g of Methocel A15 (methylcellulose/Dow) and 0.25 g of magnesium stearate are mixed and then tableted. The mass of the tablets is 655 mg.

The tests for dissolution of these tablets in 900 ml of 0.1N HCl and (40% EtOH; 60% 0.1N HCl) are reported in FIG. 3. It is noted that the release in an alcoholic medium is slower than in an aqueous medium.

Example 7 Preparation According to the Invention of Anti-Crushing Microparticles of Oxycodone HCl

Granules:

1582.7 g of oxycodone HCl are added to a solution containing 83.3 g of Plasdone K29/32 (povidone/Dow), 2011.1 g of demineralized water and 1082.9 g of ethanol. The mixture is stirred at 67° C. The solution is then sprayed, in a Glatt GPCG 1.1 fluidized air bed device, onto 300 g of particles of cellulose spheres (Asahi-Kasei). The product recovered is then sifted on 80-300 μm.

Microparticles:

450 g of the granules prepared as indicated above are then film-coated, in a Glatt GPCG 1.1 fluidized air bed device, with a solution containing 315 g of Ethocel 20 Premium (ethylcellulose/Dow), 36 g of Plasdone K29/32 (povidone/ISP), 54 g of Lutrol F-68 (Poloxamer 188/BASF), 45 g of castor oil (Garbit huilerie), 3105 g of acetone and 2070 g of isopropanol. The mass of the coating represents 50% of the total mass of the MR microparticle of oxycodone HCl.

Example 8 Preparation of Tablets According to the Invention

11 g of microparticles of oxycodone prepared in Example 7, 4 g of Amberlite IR69F (Rhom & Haas) sifted between 160 and 300 μm, 2 g of Polyox WSR 303, 8 g of talc (Luzenac 00), 4 g of Methocel A15 (methylcellulose/Dow) and 0.5 g of magnesium stearate are mixed and then tableted. The mass of the tablets is 590 mg.

The tests for dissolution of these tablets in 900 ml of 0.1N HCl and (10% EtOH; 90% 0.1N HCl) are reported in FIG. 4. The rate of release in a medium containing 10% of ethanol is comparable to or even slower than that obtained in a purely aqueous medium.

Example 9 Preparation of Tablets According to the Invention

11 g of microparticles of oxycodone prepared in Example 7, 4 g of Amberlite IR69F (Rhom & Haas) crushed and sifted between 160 and 300 μm, 2 g of polyethylene oxide (Polyox WSR 303/Sentry), 5 g of talc (Luzenac 00), 2 g of methylcellulose (Methocel A15/Dow), 2 g of hydroxyethylcellulose (Natrosol 250G/Aqualon), 3 g of microcrystalline cellulose (Avicel PH200/FMC) and 0.5 g of magnesium stearate are mixed and then tableted. The mass of the tablets is 590 mg.

The tests for dissolution of these tablets in 900 ml of 0.1N HCl and (10% EtOH; 90% 0.1N HCl) are reported in FIG. 5. The rate of release in a medium containing 10% of ethanol is comparable to or even slower than that obtained in a purely aqueous medium.

Example 10 Preparation of Tablets According to the Invention

10 g of microparticles of oxycodone prepared in Example 1, 5 g of Amberlite IR69F (Rhom & Haas) crushed and sifted between 160 and 300 μm, 2.5 g of polyethylene oxide (Polyox WSR 303/Sentry), 10 g of microcrystalline cellulose (Avicel PH101/FMC), 2.5 g of hypromellose (Methocel E15/Dow), 2.5 g of hypromellose (Methocel E5/Dow), and 0.25 g of magnesium stearate are mixed and then tableted. The mass of the tablets is 655 mg.

The tests for dissolution of these tablets in 900 ml of 0.1N HCl and (40% EtOH; 60% 0.1N HCl) are reported in FIG. 6.

Example 11 Preparation According to the Invention of Anti-Crushing Microparticles of Oxycodone HCl

Granules:

1615 g of oxycodone HCl are added to a solution containing 85 g of povidone (Plasdone K29/32/ISP), 2052 g of demineralized water and 1105 g of ethanol. The mixture is stirred at 67° C. The solution is then sprayed, in a Glatt GPCG 1.1 fluidized air bed device, onto 300 g of particles of cellulose spheres (Cellets 90/Pharmatrans). The product recovered is then sifted on 80-250 μm.

Microparticles:

450 g of the granules prepared as indicated above are then film-coated, in a Glatt GPCG 1.1 fluidized air bed device, with a solution containing 315 g of ethylcellulose (Ethocel 20 Premium/Dow), 54 g of povidone (Plasdone K29/32/ISP), 27 g of PEG40 hydrogenated castor oil (Cremophor RH 40/BASF), 54 g of castor oil (Garbit huilerie), 3105 g of acetone and 2070 g of isopropanol. The mass of the coating represents 50% of the total mass of the MR microparticle of oxycodone HCl.

Example 12 Preparation of Tablets According to the Invention

55 mg of microparticles of oxycodone prepared in Example 11, 20 mg of Amberlite IR69F (Rhom & Haas) sifted between 160 and 300 μm, 40 mg of polyethylene oxide (Polyox WSR 303/Sentry), 120 mg of microcrystalline cellulose (Avicel PH301/FMC), 10 mg of methylcellulose (Methocel A15LV/Dow), 5 mg of hydroxypropylcellulose (Klucel HXF/Aqualon), 5 mg of magnesium stearate, 185 mg of mannitol (Pearlitol SD200/Roquette) and 25 mg of sodium bicarbonate (Merck) are mixed and then tableted with a Korsch XP-1 press.

These tablets have a slower release kinetics in a 20% v/v ethanol medium than in a 0.1N HCl medium (FIG. 7). 

1.-69. (canceled)
 70. A tablet comprising: i) coated modified release microparticles comprising at least one active principle (AP), and ii) a pharmaceutically acceptable compound of which the rate of hydration or of solvation or the ability to hydrate or to solvate is greater in an aqueous medium free of alcohol than in an alcoholic solution, said compound being named agent D, wherein the agent D is present in a mixture with the coated modified release microparticles of AP or is included in a coating deposited onto the tablet, wherein the coated modified release microparticles of AP comprise a core comprising said AP, said core being coated with at least one coating R, wherein the coating R represents at least 30% by weight on dry basis, relative to the total weight of the coated modified release microparticles of AP, and comprises by weight relative to the total weight of the coating R: 60 to 90% of a film-forming (co)polymer A1 which is insoluble in the fluids of the gastrointestinal tract; 2 to 40% of a (co)polymer A2 which is soluble in the fluids of the gastrointestinal tract; and 1 to 30% of a plasticizer A3. wherein the time for releasing 50% of the AP in an alcoholic solution is not decreased by more than threefold compared to the time for releasing 50% of the AP in an aqueous medium free of alcohol.
 71. The tablet according to claim 70, wherein in the event of crushing, the modified release is maintained for at least 40% of the coated modified release microparticles of AP.
 72. The tablet according to claim 70, wherein in the event of crushing, the modified release is maintained for at least 60% of the coated modified release microparticles of AP.
 73. The tablet according to claim 70, wherein in the event of crushing, the modified release is maintained for at least 80% of the coated modified release microparticles of AP.
 74. The tablet according to claim 70, wherein the agent D is chosen from the group consisting of: cellulose derivatives, polyalkylene oxides, polysaccharides, proteins, clays and mixtures thereof.
 75. The tablet according to claim 74, wherein the agent D is chosen from the group consisting of: methylcelluloses, (hydroxy)(alkyl)celluloses, carboxyalkylcelluloses and salts thereof, celluloses, crosslinked carboxyalkylcelluloses, polyethylene oxide, polypropylene oxide natural starches, modified starches, alginates and salts thereof, polacrilin potassium, guar gums, carrageenans, pullulans, pectins, chitosans and derivatives thereof, gelatins, albumins, caseins, lactoglobulins, bentonite, laponite, and mixtures thereof.
 76. The tablet according to claim 75, wherein the agent D is chosen from the group consisting of: hydroxypropylcellulose, hydroxypropylmethylcellulose, hydroxyethylcellulose; carboxymethylcellulose and salts thereof; cellulose powder, cellulose microcrystalline; crosslinked carboxymethylcelluloses; starch of maize, starch of wheat, starch of potato; starches modified with sodium glycolate sodium alginate and mixtures thereof.
 77. The tablet according to claim 76, wherein the agent D is sodium croscarmellose.
 78. The tablet according to claim 70, wherein the agent D is present in a mixture with the coated modified release microparticles of AP and included in the binding phase of granules or pellets including the coated modified release microparticles of AP.
 79. The tablet according to claim 78, wherein the granules or pellets are obtained by granulation, extrusion or compression.
 80. The tablet according to claim 70, wherein the agent D is present in a proportion of 1% to 30% w/w of the total weight of the tablet.
 81. The tablet according to claim 70, wherein the agent D is present in a proportion of 2% to 25% w/w of the total weight of the tablet.
 82. The tablet according to claim 70, wherein the agent D is present in a proportion of 2% to 20% w/w, of the total weight of the tablet.
 83. The tablet according to claim 70, wherein A1 represents 60% to 80% by weight, relative to the weight of the coating R.
 84. The tablet according to claim 70, wherein A2 represents 5% to 40% by weight, relative to the weight of the coating R.
 85. The tablet according to claim 70, wherein A2 represents 5% to 25% by weight, relative to the weight of the coating R.
 86. The tablet according to claim 70, wherein A3 represents 2% to 20% by weight, relative to the weight of the coating R.
 87. The tablet according to claim 70, wherein A3 represents 5% to 15% by weight, relative to the weight of the coating R.
 88. The tablet according to claim 70, wherein A1 is selected from the group consisting of: water-insoluble derivatives of cellulose, acrylic polymers, poly(vinyl acetate)s, and mixtures thereof.
 89. The tablet according to claim 88, wherein A1 is selected from the group consisting of: ethylcellulose and cellulose acetates, copolymers of (meth)acrylic acid and of alkyl ester and copolymers of an ester of acrylic acid and methacrylic acid bearing at least one quaternary ammonium group, copolymers of alkyl (meth)acrylate and trimethylammonioethyl methacrylate chloride.
 90. The tablet according to claim 70, wherein A2 is selected from the group consisting of: nitrogenous (co)polymers, water-soluble derivatives of cellulose, polyvinyl alcohols (PVAs), polyalkylene oxides, polyethylene glycols (PEGs), and mixtures thereof.
 91. The tablet according to claim 90, wherein A2 is selected from the group consisting of: polyacrylamides, poly-N-vinylamides, polyvinylpyrrolidones (PVPs) and poly-N-vinyllactams.
 92. The tablet according to claim 70, wherein A3 is selected from the group consisting of: cetyl alcohol esters, glycerol and esters thereof, phthalates, citrates, sebacates, adipates, azelates, benzoates, plant oils, fumarates, malates, oxalates, succinates, butyrates, malonates, castor oil and mixtures thereof.
 93. The tablet according to claim 70, wherein: A1 is selected from the group consisting of water-insoluble derivatives of cellulose; A2 is selected from the group consisting of: nitrogenous(co)polymers, water-soluble derivatives of cellulose, polyethylene glycols (PEGs), and mixtures thereof; A3 is selected from the group consisting of: triethyl citrate, dibutyl sebacate, plant oils, castor oil and mixtures thereof.
 94. The tablet according to claim 70, wherein the coating R further comprises at least one surfactant, lubricant, mineral filler or organic filler A4.
 95. The tablet according to claim 94, wherein A4 represents less than or equal to 40% by weight, relative to the weight of the coating R.
 96. The tablet according to claim 94, wherein A4 represents less than or equal to 20% by weight, relative to the weight of the coating R.
 97. The tablet according to claim 94, wherein A4 is selected from the group consisting of: anionic surfactants, nonionic surfactants, stearates, stearyl fumarates, glycerol behenates, talc, colloidal silica, titanium oxide, magnesium oxide, bentonite, microcrystalline cellulose, kaolin, aluminum silicate, and mixtures thereof.
 98. The tablet according to claim 97, wherein A4 is selected from the group consisting of: alkali metal and alkaline earth metal salts of fatty acids; polyoxyethylenated oils; polyoxyethylene/polyoxypropylene copolymers (poloxamer); polyoxyethylenated sorbitan esters; polysorbates and polyoxyethylenated castor oil derivatives; calcium stearate, magnesium stearate, aluminum stearate and zinc stearate.
 99. The tablet according to claim 98, wherein A4 is polyoxyethylenated hydrogenated castor oil.
 100. The tablet according to claim 70, wherein the coating R represents 30% to 60% by weight on dry basis, of the total weight of the coated modified release microparticles of AP.
 101. The tablet according to claim 70, wherein the coating R represents 40% to 60% by weight on dry basis, of the total weight of the coated modified release microparticles of AP.
 102. The tablet according to claim 70, wherein the coating R represents 45% to 55% by weight on dry basis, of the total weight of the coated modified release microparticles of AP.
 103. The tablet according to claim 70, wherein the coating R is a single coating layer.
 104. The tablet according to claim 70, wherein the core comprising said AP is: a matrix granule containing said AP and other pharmaceutically acceptable excipients; or a support particle coated with at least one layer comprising said AP.
 105. The tablet according to claim 104, wherein the pharmaceutically acceptable excipients of the matrix granule are selected from the group consisting of: binders, surfactants, disintegrating agents, fillers and buffering agent.
 106. The tablet according to claim 104, wherein the support particle is a cellulose microsphere or a particle comprising at least one of the compounds selected from the group consisting of: sucrose, saccharose, dextrose, lactose, mixture of sucrose and starch, xanthan gum, guar gum, calcium phosphate and calcium carbonate.
 107. The tablet according to claim 104, wherein the mean diameter of the support particles is from 1 to 800 μm.
 108. The tablet according to claim 104, wherein the mean diameter of the support particles is from 20 to 500 μm.
 109. The tablet according to claim 70, wherein the coated modified release microparticles of AP have a volume-average diameter of less than or equal to 1000 μm.
 110. The tablet according to claim 70, wherein the coated modified release microparticles of AP have a volume-average diameter of 50 to 800 μm.
 111. The tablet according to claim 70, wherein the coated modified release microparticles of AP have a volume-average diameter of 100 to 600 μm.
 112. The tablet according to claim 70, wherein the coated modified release microparticles of AP have a volume-average diameter of 100 to 400 μm.
 113. The tablet according to claim 70, further comprising at least one viscosity-modifying agent V.
 114. The tablet according to claim 113, wherein the viscosity-modifying agent V is in the form of microparticles distinct from the coated modified release microparticles of AP.
 115. The tablet according to claim 113, wherein the viscosity-modifying agent V is chosen from viscosity-modifying agents which are soluble in at least one of the following extraction solvents: water, alcohols, ketones, and mixtures thereof.
 116. The tablet according to claim 113, wherein the viscosity-modifying agent V is chosen from the group consisting of: poly(meth)acrylic acid and derivatives thereof, polyalkylene glycols, polyalkylene oxides, polyvinylpyrrolidones, gelatins, polysaccharides and mixtures thereof.
 117. The tablet according to claim 116, wherein the viscosity-modifying agent V is chosen from the group consisting of: sodium alginate, pectins, guars, xanthans, carrageenans, gellans, and cellulose derivatives.
 118. The tablet according to claim 117, wherein the viscosity-modifying agent V is chosen from the group consisting of: hydroxypropylmethylcellulose, methylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, carboxymethylcellulose.
 119. The tablet according to claim 113, wherein the viscosity-modifying agent V is polyoxyethylene having a molecular weight of 1 million g/mol to 8 million g/mol.
 120. The tablet according to claim 113, wherein the amount of viscosity-modifying agent V in the tablet is adjusted so as to render the viscosity of 2.5 ml of the extraction solvent greater than or equal to 100 mPa·s.
 121. The tablet according to claim 113, wherein the quantity of viscosity-modifying agent V from 2 to 400 mg.
 122. The tablet according to claim 113, wherein the quantity of viscosity-modifying agent V is from 5 to 200 mg.
 123. The tablet according to claim 113, wherein the quantity of viscosity-modifying agent V is from 10 to 100 mg.
 124. The tablet according to claim 70, further comprising at least one quenching agent Q.
 125. The tablet according to claim 124, wherein the quenching agent Q is in the form of microparticles distinct from the coated modified release microparticles of AP.
 126. The tablet according to claim 124, wherein the quenching agent Q is in a non-complexed form regarding the AP within the tablet.
 127. The tablet according to claim 124, wherein the quenching agent Q comprises a salt, which contains ions capable of forming a complex with salt of AP extracted in solution.
 128. The tablet according to claim 127, wherein the ions of the quenching agent Q are organic ions of polarity opposite to that of the AP in solution.
 129. The tablet according to claim 124, wherein the quenching agent Q is a ion exchange resin or comprises a salt selected from the group consisting of: anionic organic salts, anionic polymers, monovalent or polyvalent salts, saponified fatty acids, polyamino acids, proteins, peptides, metal cationic salts, organic cationic salts, cationic polymers, and mixtures thereof.
 130. The tablet according to claim 129, wherein the quenching agent Q comprises a salt selected from the group consisting of: sodium dodecyl sulfate, sodium docusate; anionic (meth)acrylic copolymers, crosslinked polyacrylic acids, carboxymethylcellulose and its derivatives, crosslinked carboxymethylcellulose and its derivatives, polysaccharides, alginate (sulfonate) propylene glycol; salts of glucuronates, citrates, acetates, carbonates, gluconates, succinates, phosphates, glycerophosphates, lactates, trisilicates, fumarates, adipates, benzoates, salicylates, tartrates, sulfonamides, acesulfames; salts of Ca, Fe, Mg and Zn in the form of chlorides, fluorides, hydroxides, iodates, iodides, oxides; salts of acetic acid, succinic acid, citric acid, stearic acid, palmitic acid, and self-emulsifying glycerylmonooleates; trimethyltetradecyl ammonium, bromide or benzethonium chloride; chitosan and cationic(meth)acrylic copolymers; anionic and cationic polyamino acids, proteins or peptides; and mixtures thereof.
 131. The tablet according to claim 130, wherein the quenching agent Q selected from the group consisting of: alginate, xanthan gum and gum Arabic.
 132. The tablet according to claim 124, wherein the quenching agent Q is chosen from: cation exchange resins or anion exchange resins, depending on the polarity of the AP.
 133. The tablet according to claim 124, wherein the quenching agent Q is a derivative of a styrene/divinylbenzene copolymer, a derivative of a sulfonic styrene/divinylbenzene copolymer, a derivative of styrene/divinylbenzene copolymer bearing quaternary ammonium functions, a crosslinked copolymer of methacrylic acid and of divinylbenzene or a salt thereof, a phenolic polyamine, or a mixture thereof.
 134. The tablet according to claim 124, wherein the quenching agent Q is chosen from: sodium dodecyl sulfate, sodium docusate, trimethyltetradecyl ammonium, bromide or benzethonium chloride and cation exchange resins or anion exchange resins, depending on the polarity of the AP.
 135. The tablet according to claim 124, wherein the amount of quenching agent is adjusted so as to complex all or part of the dose of AP contained in the unit form.
 136. The tablet according to claim 70, further comprising at least one pharmaceutically acceptable excipient not contained in or supported by coated modified release microparticles of AP, said excipient contributing to the resistance of crushing of the coated modified release microparticles of AP and selected from the group consisting of: calcium stearate, glyceryl behenate, glyceryl palmitostearate, magnesium oxide, polyalkylene glycols, polyvinyl alcohol, sodium benzoate, stearic acid, corn starch, talc, colloidal silica, zinc stearate, magnesium stearate, stearyl fumarate, and mixtures thereof.
 137. The tablet according to claim 70, comprising at least 500 coated modified release microparticles of AP.
 138. The tablet according to claim 70, comprising from 1000 to 1 000 000 coated modified release microparticles of AP.
 139. The tablet according to claim 70, comprising from 5000 to 500 000 coated modified release microparticles of AP.
 140. The tablet according to claim 70, comprising a plurality of populations of coated modified release microparticles of AP, said populations differing from one another by virtue of their release kinetics or by virtue of the AP that they contain.
 141. The tablet according to claim 70, comprising coated modified release microparticles of AP and immediate-release microparticles of AP.
 142. The tablet according to claim 70, comprising an ion exchange resin, polyoxyethylene and wherein agent D is methylcellulose.
 143. The tablet according to claim 70 comprising an ion exchange resin, polyoxyethylene and wherein agent D is a mixture of methylcellulose and hydroxyethylcellulose.
 144. The tablet according to claim 70 comprising an ion exchange resin, polyoxyethylene and wherein agent D is a mixture of methylcellulose and hydroxypropylcellulose.
 145. The tablet according to claim 70 comprising an ion exchange resin, polyoxyethylene and wherein agent D is hydroxypropyl methylcellulose.
 146. The tablet according to claim 70 comprising 2 to 400 mg of a viscosity-modifying agent V contained in microparticles distinct from the coated modified release microparticles of AP and at least one quenching agent Q contained in microparticles distinct from the coated modified release microparticles of AP and from the viscosity agent microparticles.
 147. The tablet according to claim 146, wherein: A1 is selected from the group consisting of water-insoluble derivatives of cellulose; A2 is selected from the group consisting of: nitrogenous (co)polymers, water-soluble derivatives of cellulose, polyethylene glycols (PEGs), and mixtures thereof; A3 selected from the group consisting of: triethyl citrate, dibutyl sebacate, plant oils, castor oil, and mixtures thereof; the agent D is selected from the group consisting of: hydroxyalkylcelluloses, methylcellulose, carboxy(alkyl)celluloses, and salts thereof, guar gums, carrageenans and mixtures thereof; the viscosity-modifying agent V is chosen from: polyalkylene oxides, xanthans, cellulose derivatives and mixtures thereof; the quenching agent Q is selected from the group consisting of: dodecyl sulfate, sodium docusate, trimethyltetradecyl anmmonium bromide, benzethonium chloride and ion exchange resins.
 148. The tablet according to claim 70, wherein the active principle AP is selected from the group consisting of: opiates, anxiolytics, benzodiazepines, anorexigens, antidepressants, antiepileptics, antiparkinsonian agents, barbiturates, hypnotics, neuroleptics, psychostimulants, psychotropic agents, amphetamines and mixtures thereof.
 149. The tablet according to claim 70, wherein the AP is chosen from the group consisting of: acetorphine, acetyl-alpha-methylfentanyl, acetyldihydrocodeine, acetylmethadol, alfentanil, allylprodine, alpha-cetylmethadol, alphameprodine, alphaprodine, alphamethadol, alpha-methylfentanyl, alphamethylthiofentanyl, anileridine, butorphanol, benzethidine, benzylmorphine, beta-hydroxyfentanyl, beta-hydroxymethyl-3-fentanyl, beta-cetylmethadol, betameprodine, betamethadol, betaprodine, bezitramide, buprenorphine, dioxaphetyl butyrate, clonitazene, cyclazocine, cannabis, codeine, coca, cocaine, codoxime, dezocine, dimenoxadol, dipipanone, desomorphine, dextromoramide, dextropropoxyphene, diampromide, diethylthiambutene, difenoxin, dihydrocodeine, dihydroetorphine, dihydromorphine, dimenoxadol, dimepheptanol, dimethylthiambutene, diphenoxylate, dipipanone, drotebanol, eptazocine, ethoheptazine, ethylmethylthiambutene, ethylmorphine, etonitazene, ethylmethylthiambutene, ethylmorphine, etorphine, etoxeridine, fentanyl, furethidine, heroin, hydrocodone, hydromorphinol, hydromorphone, hydroxypethidine, isomethadone, ketobemidone, levallorphan, lofentanil, levomethorphan, levomoramide, levophenacylmorphan, levorphanol, meptazinol, meperidine, metazocine, methadone, methyldesorphine, methyldihydromorphine, methylphenidate, methyl-3-thiofentanyl, methyl-3-fentanyl, metopon, moramide, morpheridine, morphine, myrophine, nalbuphine, narceine, norlevorphanol, normethadone, nalorphine, normorphine, nicocodine, nicodicodine, nicomorphine, noracymethadol, norcodeine, norpipanone, opium, oxycodone, oxymorphone, papaveretum, phenadoxone, phenoperidine, promedol, properidine, propiram, propoxyphene, parafluorofentanyl, pentazocine, pethidine, phenampromide, phenazocine, phenomorphan, phenoperidine, pholcodine, piminodine, piritramide, proheptazine, racemethorphan, racemoramide, racemorphan, remifentanil, sufentanil, thebacone, thebaine, thiofentanyl, tilidine, trimeperidine, tramadol, and the pharmacologically acceptable salts, esters, hydrates, polymorphs and isomers thereof, and mixtures thereof.
 150. The tablet according to claim 70, wherein the AP is selected from the group consisting of: oxycodone hydrochloride, morphine sulfate, oxymorphone hydrochloride, hydromorphone hydrochloride, hydrocodone hydrochloride and tramadol hydrochloride. 